Firth starred in Allen's 2013 film Magic in the Moonlight alongside Emma Stone, and adds his name to a number of actors who have worked under the director to have now expressed their regret at doing so, including Rebecca Hall, Timothee Chalamet, Mira Sorvino, Rachel Brosnahan and Greta Gerwig. Hall and Chalamet have both said they would donate their salaries from Allen's upcoming film A Rainy Day in New York to charities.

Last year, Firth was outspoken about Harvey Weinstein, who produced his Oscar-winning 2010 film The King's Speech, describing him as a "frightening man."